ECG Hypertrophy of Atria and Ventricles (Johnston)

Question 1

Atrial Enlargement occurs because of either an

Answer 1

• Increase in volume of blood in the chamber or
• Increase in resistance to blood flow out of chamber
• Volume overload or diastolic overload–dilation
• Pressure overload or systolic overload–causes hypertrophy

Question 2

Leads to recognize for atrial enlargement;

R vs L atrial activation

Answer 2

• Leads I, II, III and V1

- RA activated first, LA activated later!!

Question 3

Normal morphology of P wave

Answer 3

• represents atrial depolarization
• should be rounded contour (not pointed, tall peaked or notched, wide and M shaped)
• Should not exceed 3 mm

Question 4

Increased amplitude of P wave indicates

Answer 4

-hypertrophy, HTN, AV valve disease, for pulmonale, congenital

Question 5

RAE morphology on ECG

Answer 5

-p wave tall, pointed, taller in III than in I: P-pulmonale

Question 6

LAE morphology on ECG

Answer 6

• p wave wide, notched; taller in I than in III
• P-mitrale
• 2nd half of P wave negative in V1 or III

Question 7

RAE associated with

Answer 7

• Tricuspid Valve disease or pulmonary HTN

- COPD, PE, Mitral Stenosis or Mitral Regurg are causes of pulmonary HTN

Question 8

RAE

Answer 8

• P-pulmonale peaked P wave with amplitude greater than 0.25 (2.5 mm) mv in leads II, III, AVF and greater than 0.1 mv in leads V1 and V2
• P wave has slight rightward axis

Question 9

Right deviation seen in

Answer 9

• Lung disease
• Tall, thin, and tear shaped cardiac silhouette
• Especially seen in emphysema

Question 10

LAE

Answer 10

• P-mitrale
• M signs to P wave, broad, notched P wave duration 0.11 sec and amplitude of terminal negatively directed portion in V1 to greater than 0.1 mV or 1 mm deep and 0.04 sec wide with slight axis of P wave

Question 11

Causes of LAE

Answer 11

-Mitral stenosis or Mitral Regurg

Question 12

inverted P waves before QRS complex in leads I, II and III think what?

Answer 12

• Low atrial junctional rhythm

- Also see upright p wave in AVR; but inversion of p waves in I, II and III

Question 13

Most common cause of LVH is? Other causes

Answer 13

MCC: HTN

-Other causes: Aortic stenosis, Aortic insufficiency, Hypertrophic cardiomyopathy, and coarctation of aorta

Question 14

Features of LVH

Answer 14

• Wall of LV is thicker so impulse will take longer to traverse it and arrive at epicardial surface
• Voltage and interval of QRS complex will increase, producing deeper S waves over RV and taller R waves over LV

Question 15

ECG pattern of LVH fails to distinguish between

Answer 15

• concentric hypertrophy and dilated chamber so better to refer to as ventricular enlargement
• ECG can’t distinguish because it is total muscle mass of ventricle that mainly determines QRS voltage

Question 16

Criteria for LVH–sensitivity and specificity

Answer 16

-sensitivity low–40-50% but are specific (high–90%)

Question 17

Sokolow Lyon Criteria for LVH

Answer 17

• R in I + S in III > 25 mm
• R in AVL > 11mm
• R in V6 > 26 mm
• Called “Strain pattern”

Question 18

RVH causes

Answer 18

-Chronic lund disease–COPD
-RVOT obstruction, VSD
Congenital–TOF, pulmonic stenosis, Transposition of great vessels
-Long standing Mitral stenosis, tricuspid regurgitation

Question 19

RVH morphology

Answer 19

• R waves assume prominence in right precordial leads and deep S waves develop in left precordial leads
• R:S ratio greater than 1

Question 20

Clues to RVH

Answer 20

-RAD + 90 OR MORE
-R in V1 is 7 mm or more
-R in V1 + S in V6 10 mm or more
R/S ratio in V1 >1 or more
-S/R ratio in V6 >1 or more
-Late intrinsic deflection in V1 0.03 or more
-Incomplete RBBB
-ST-T strain pattern in II, III, AVF
-P pulmonale
-S1 S2 S3 pattern (children)

Question 21

Causes of dominant R waves in V1

Answer 21

• RVH
• Posterior or lateral MI
• WPW
• Hypertrophic cardiomyopathy
• Muscular dystrophy
• Normal variant